Treatment of hides and skins preliminary to tanning



Patented Nov. 1, 1927.

UNITEDSTATES RENE BOTSON, or AUDERGHEM-BRUSSELS, BELGIUM.

TREATMENT OF RIDES AND SKINS PRELIMINARY TO TANNING.

No Drawing. Application filed May 21, 1927, Serial No, 193,381, and in Belgium .Tune 2, 1926.

The present invention relates to the treatment of hides and skins preliminary to tanning and has for its object the neutralization of same after they have been unhaire'd and before their introduction in the tanning bath.

Chemical processes for unhairing hides and skins are well known, as for instance using, a solution of steam refined sodium sulphide and caustic alkali with water. It is.

often preferred to have the hides and skins, after depil ,tion, completely neutralized and specially freed from any particle of lime they may contain.

Up to now, weak acid baths were generally used for the elimination of lime out of unhaired hides and skins, but it has been found that a weak acid bath containing a proportion of nitro-benzol produces a particularly efilcient result, so that all mineral impurities will be entirely eliminated.

Following the nature of the hide, the novel treatment will, for-instance, comprise a soakin'g, during 2 to 24 hours, in a bath constituted with acetic acid containing in solution of nitro-benzol, the bath being formed with one part of acid and two thousand parts of water. In these conditions complete 2. Neutralizing bath for unhaired hides and skinsconstituted with one part of acetic acid and two thousand parts of water, the acid containing one part per thousand of nitro-benzol.

In testimony whereof I signed hereunto my name.

RENE BOTSON. 

